diff --git a/src/main/java/com/google/api/generator/gapic/model/Field.java b/src/main/java/com/google/api/generator/gapic/model/Field.java
index 8f6d10b2af..57d836979e 100644
--- a/src/main/java/com/google/api/generator/gapic/model/Field.java
+++ b/src/main/java/com/google/api/generator/gapic/model/Field.java
@@ -31,6 +31,13 @@ public abstract class Field {
   @Nullable
   public abstract ResourceReference resourceReference();
 
+  @Nullable
+  public abstract String description();
+
+  public boolean hasDescription() {
+    return description() != null;
+  }
+
   public boolean hasResourceReference() {
     return type().equals(TypeNode.STRING) && resourceReference() != null;
   }
@@ -51,6 +58,8 @@ public abstract static class Builder {
 
     public abstract Builder setResourceReference(ResourceReference resourceReference);
 
+    public abstract Builder setDescription(String description);
+
     public abstract Field build();
   }
 }
diff --git a/src/main/java/com/google/api/generator/gapic/model/Method.java b/src/main/java/com/google/api/generator/gapic/model/Method.java
index eb77f15a1c..30e94c9ad5 100644
--- a/src/main/java/com/google/api/generator/gapic/model/Method.java
+++ b/src/main/java/com/google/api/generator/gapic/model/Method.java
@@ -42,6 +42,9 @@ public enum Stream {
   @Nullable
   public abstract LongrunningOperation lro();
 
+  @Nullable
+  public abstract String description();
+
   // Example from Expand in echo.proto: Thet TypeNodes that map to
   // [["content", "error"], ["content", "error", "info"]].
   public abstract ImmutableList<List<MethodArgument>> methodSignatures();
@@ -50,7 +53,9 @@ public boolean hasLro() {
     return lro() != null;
   }
 
-  // TODO(miraleung): Parse annotations, comments.
+  public boolean hasDescription() {
+    return description() != null;
+  }
 
   public static Builder builder() {
     return new AutoValue_Method.Builder()
@@ -84,6 +89,8 @@ public abstract static class Builder {
 
     public abstract Builder setLro(LongrunningOperation lro);
 
+    public abstract Builder setDescription(String description);
+
     public abstract Builder setMethodSignatures(List<List<MethodArgument>> methodSignature);
 
     public abstract Builder setIsPaged(boolean isPaged);
diff --git a/src/main/java/com/google/api/generator/gapic/model/MethodArgument.java b/src/main/java/com/google/api/generator/gapic/model/MethodArgument.java
index 685f7b4685..f7ce9ad2b9 100644
--- a/src/main/java/com/google/api/generator/gapic/model/MethodArgument.java
+++ b/src/main/java/com/google/api/generator/gapic/model/MethodArgument.java
@@ -18,6 +18,7 @@
 import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
+import javax.annotation.Nullable;
 
 @AutoValue
 public abstract class MethodArgument implements Comparable<MethodArgument> {
@@ -32,6 +33,13 @@ public abstract class MethodArgument implements Comparable<MethodArgument> {
   // Returns true if this is a resource name helper tyep.
   public abstract boolean isResourceNameHelper();
 
+  @Nullable
+  public abstract String description();
+
+  public boolean hasDescription() {
+    return description() != null;
+  }
+
   @Override
   public int compareTo(MethodArgument other) {
     int compareVal = type().compareTo(other.type());
@@ -57,6 +65,8 @@ public abstract static class Builder {
 
     public abstract Builder setIsResourceNameHelper(boolean isResourceNameHelper);
 
+    public abstract Builder setDescription(String description);
+
     public abstract MethodArgument build();
   }
 }
diff --git a/src/main/java/com/google/api/generator/gapic/model/ResourceName.java b/src/main/java/com/google/api/generator/gapic/model/ResourceName.java
index 45e8e1c814..14770b7366 100644
--- a/src/main/java/com/google/api/generator/gapic/model/ResourceName.java
+++ b/src/main/java/com/google/api/generator/gapic/model/ResourceName.java
@@ -54,10 +54,17 @@ public abstract class ResourceName {
   @Nullable
   public abstract String parentMessageName();
 
+  @Nullable
+  public abstract String description();
+
   public boolean hasParentMessageName() {
     return parentMessageName() != null;
   }
 
+  public boolean hasDescription() {
+    return description() != null;
+  }
+
   public String resourceTypeName() {
     return resourceTypeString().substring(resourceTypeString().indexOf(SLASH) + 1);
   }
@@ -92,6 +99,7 @@ public boolean equals(Object o) {
     }
 
     ResourceName other = (ResourceName) o;
+    // Exclude the description from the resource name because it's just a comment.
     return variableName().equals(other.variableName())
         && pakkage().equals(other.pakkage())
         && resourceTypeString().equals(other.resourceTypeString())
@@ -125,6 +133,8 @@ public abstract static class Builder {
 
     public abstract Builder setParentMessageName(String parentMessageName);
 
+    public abstract Builder setDescription(String description);
+
     // Private setters.
     abstract Builder setType(TypeNode type);
 
diff --git a/src/main/java/com/google/api/generator/gapic/protoparser/MethodSignatureParser.java b/src/main/java/com/google/api/generator/gapic/protoparser/MethodSignatureParser.java
index d7d20e5265..baef34d268 100644
--- a/src/main/java/com/google/api/generator/gapic/protoparser/MethodSignatureParser.java
+++ b/src/main/java/com/google/api/generator/gapic/protoparser/MethodSignatureParser.java
@@ -25,7 +25,6 @@
 import com.google.common.collect.Lists;
 import com.google.protobuf.Descriptors.MethodDescriptor;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -68,8 +67,8 @@ public static List<List<MethodArgument>> parseMethodSignatures(
         // For resource names, this will be empty.
         List<TypeNode> argumentTypePathAcc = new ArrayList<>();
         // There should be more than one type returned only when we encounter a reousrce name.
-        List<TypeNode> argumentTypes =
-            parseTypeFromArgumentName(
+        Map<TypeNode, String> argumentTypes =
+            parseTypeAndCommentFromArgumentName(
                 argumentName,
                 servicePackage,
                 inputMessage,
@@ -84,14 +83,15 @@ public static List<List<MethodArgument>> parseMethodSignatures(
         argumentNames.add(actualArgumentName);
         argumentNameToOverloads.put(
             actualArgumentName,
-            argumentTypes.stream()
+            argumentTypes.entrySet().stream()
                 .map(
-                    type ->
+                    e ->
                         MethodArgument.builder()
                             .setName(actualArgumentName)
-                            .setType(type)
+                            .setDescription(e.getValue()) // May be null.
+                            .setType(e.getKey())
                             .setIsResourceNameHelper(
-                                argumentTypes.size() > 1 && !type.equals(TypeNode.STRING))
+                                argumentTypes.size() > 1 && !e.getKey().equals(TypeNode.STRING))
                             .setNestedTypes(argumentTypePathAcc)
                             .build())
                 .collect(Collectors.toList()));
@@ -143,7 +143,7 @@ private static List<List<MethodArgument>> flattenMethodSignatureVariants(
     return methodArgs;
   }
 
-  private static List<TypeNode> parseTypeFromArgumentName(
+  private static Map<TypeNode, String> parseTypeAndCommentFromArgumentName(
       String argumentName,
       String servicePackage,
       Message inputMessage,
@@ -153,6 +153,8 @@ private static List<TypeNode> parseTypeFromArgumentName(
       List<TypeNode> argumentTypePathAcc,
       Set<ResourceName> outputArgResourceNames) {
 
+    // Comment values may be null.
+    Map<TypeNode, String> typeToComment = new HashMap<>();
     int dotIndex = argumentName.indexOf(DOT);
     if (dotIndex < 1) {
       Field field = inputMessage.fieldMap().get(argumentName);
@@ -162,19 +164,27 @@ private static List<TypeNode> parseTypeFromArgumentName(
               "Field %s not found from input message %s values %s",
               argumentName, inputMessage.name(), inputMessage.fieldMap().keySet()));
       if (!field.hasResourceReference()) {
-        return Arrays.asList(field.type());
+        typeToComment.put(field.type(), field.description());
+        return typeToComment;
       }
 
       // Parse the resource name tyeps.
       List<ResourceName> resourceNameArgs =
           ResourceReferenceParser.parseResourceNames(
-              field.resourceReference(), servicePackage, resourceNames, patternsToResourceNames);
+              field.resourceReference(),
+              servicePackage,
+              field.description(),
+              resourceNames,
+              patternsToResourceNames);
       outputArgResourceNames.addAll(resourceNameArgs);
-      List<TypeNode> allFieldTypes = new ArrayList<>();
-      allFieldTypes.add(TypeNode.STRING);
-      allFieldTypes.addAll(
-          resourceNameArgs.stream().map(r -> r.type()).collect(Collectors.toList()));
-      return allFieldTypes;
+      typeToComment.put(
+          TypeNode.STRING,
+          resourceNameArgs.isEmpty() ? null : resourceNameArgs.get(0).description());
+      typeToComment.putAll(
+          resourceNameArgs.stream()
+              .collect(
+                  Collectors.toMap(r -> r.type(), r -> r.hasDescription() ? r.description() : "")));
+      return typeToComment;
     }
 
     Preconditions.checkState(
@@ -204,7 +214,7 @@ private static List<TypeNode> parseTypeFromArgumentName(
             "Message type %s for field reference %s invalid", firstFieldTypeName, firstFieldName));
 
     argumentTypePathAcc.add(firstFieldType);
-    return parseTypeFromArgumentName(
+    return parseTypeAndCommentFromArgumentName(
         remainingArgumentName,
         servicePackage,
         firstFieldMessage,
diff --git a/src/main/java/com/google/api/generator/gapic/protoparser/Parser.java b/src/main/java/com/google/api/generator/gapic/protoparser/Parser.java
index 275ec8d5cb..c8485ad4f2 100644
--- a/src/main/java/com/google/api/generator/gapic/protoparser/Parser.java
+++ b/src/main/java/com/google/api/generator/gapic/protoparser/Parser.java
@@ -29,6 +29,7 @@
 import com.google.api.generator.gapic.model.ResourceName;
 import com.google.api.generator.gapic.model.ResourceReference;
 import com.google.api.generator.gapic.model.Service;
+import com.google.api.generator.gapic.model.SourceCodeInfoLocation;
 import com.google.api.generator.gapic.utils.ResourceNameConstants;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
@@ -55,6 +56,7 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
 import java.util.stream.Collectors;
@@ -64,6 +66,9 @@ public class Parser {
   private static final String COLON = ":";
   private static final String DEFAULT_PORT = "443";
 
+  // Allow other parsers to access this.
+  protected static final SourceCodeInfoParser SOURCE_CODE_INFO_PARSER = new SourceCodeInfoParser();
+
   static class GapicParserException extends RuntimeException {
     public GapicParserException(String errorMessage) {
       super(errorMessage);
@@ -147,7 +152,17 @@ public static List<Service> parseService(
               List<String> oauthScopes =
                   Arrays.asList(serviceOptions.getExtension(ClientProto.oauthScopes).split(COMMA));
 
-              return Service.builder()
+              Service.Builder serviceBuilder = Service.builder();
+              if (fileDescriptor.toProto().hasSourceCodeInfo()) {
+                SourceCodeInfoLocation protoServiceLocation =
+                    SOURCE_CODE_INFO_PARSER.getLocation(s);
+                if (!Objects.isNull(protoServiceLocation)
+                    && !Strings.isNullOrEmpty(protoServiceLocation.getLeadingComments())) {
+                  serviceBuilder.setDescription(protoServiceLocation.getLeadingComments());
+                }
+              }
+
+              return serviceBuilder
                   .setName(s.getName())
                   .setDefaultHost(defaultHost)
                   .setOauthScopes(oauthScopes)
@@ -244,8 +259,18 @@ static List<Method> parseMethods(
     for (MethodDescriptor protoMethod : serviceDescriptor.getMethods()) {
       // Parse the method.
       TypeNode inputType = TypeParser.parseType(protoMethod.getInputType());
+      Method.Builder methodBuilder = Method.builder();
+      if (protoMethod.getFile().toProto().hasSourceCodeInfo()) {
+        SourceCodeInfoLocation protoMethodLocation =
+            SOURCE_CODE_INFO_PARSER.getLocation(protoMethod);
+        if (!Objects.isNull(protoMethodLocation)
+            && !Strings.isNullOrEmpty(protoMethodLocation.getLeadingComments())) {
+          methodBuilder.setDescription(protoMethodLocation.getLeadingComments());
+        }
+      }
+
       methods.add(
-          Method.builder()
+          methodBuilder
               .setName(protoMethod.getName())
               .setInputType(inputType)
               .setOutputType(TypeParser.parseType(protoMethod.getOutputType()))
@@ -358,7 +383,17 @@ private static Field parseField(FieldDescriptor fieldDescriptor, Descriptor mess
       }
     }
 
-    return Field.builder()
+    Field.Builder fieldBuilder = Field.builder();
+    if (fieldDescriptor.getFile().toProto().hasSourceCodeInfo()) {
+      SourceCodeInfoLocation protoFieldLocation =
+          SOURCE_CODE_INFO_PARSER.getLocation(fieldDescriptor);
+      if (!Objects.isNull(protoFieldLocation)
+          && !Strings.isNullOrEmpty(protoFieldLocation.getLeadingComments())) {
+        fieldBuilder.setDescription(protoFieldLocation.getLeadingComments());
+      }
+    }
+
+    return fieldBuilder
         .setName(fieldDescriptor.getName())
         .setType(TypeParser.parseType(fieldDescriptor))
         .setIsRepeated(fieldDescriptor.isRepeated())
diff --git a/src/main/java/com/google/api/generator/gapic/protoparser/ResourceReferenceParser.java b/src/main/java/com/google/api/generator/gapic/protoparser/ResourceReferenceParser.java
index f81d198260..a8731deea2 100644
--- a/src/main/java/com/google/api/generator/gapic/protoparser/ResourceReferenceParser.java
+++ b/src/main/java/com/google/api/generator/gapic/protoparser/ResourceReferenceParser.java
@@ -29,6 +29,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
+import javax.annotation.Nullable;
 
 public class ResourceReferenceParser {
   private static final String EMPTY_STRING = "";
@@ -39,6 +40,7 @@ public class ResourceReferenceParser {
   public static List<ResourceName> parseResourceNames(
       ResourceReference resourceReference,
       String servicePackage,
+      @Nullable String description,
       Map<String, ResourceName> resourceNames,
       Map<String, ResourceName> patternsToResourceNames) {
     ResourceName resourceName = resourceNames.get(resourceReference.resourceTypeString());
@@ -62,6 +64,7 @@ public static List<ResourceName> parseResourceNames(
               servicePackage,
               resourceName.pakkage(),
               resourceName.resourceTypeString(),
+              description,
               patternsToResourceNames);
       // Prevent duplicates.
       if (parentResourceNameOpt.isPresent()
@@ -80,6 +83,7 @@ static Optional<ResourceName> parseParentResourceName(
       String servicePackage,
       String resourcePackage,
       String resourceTypeString,
+      @Nullable String description,
       Map<String, ResourceName> patternsToResourceNames) {
     Optional<String> parentPatternOpt = parseParentPattern(pattern);
     if (!parentPatternOpt.isPresent()) {
@@ -143,6 +147,7 @@ static Optional<ResourceName> parseParentResourceName(
             .setPakkage(pakkage)
             .setResourceTypeString(parentResourceTypeString)
             .setPatterns(Arrays.asList(parentPattern))
+            .setDescription(description)
             .build();
     patternsToResourceNames.put(parentPattern, parentResourceName);
 
diff --git a/src/test/java/com/google/api/generator/gapic/protoparser/ResourceReferenceParserTest.java b/src/test/java/com/google/api/generator/gapic/protoparser/ResourceReferenceParserTest.java
index 990e7dc4a7..c2cae61f88 100644
--- a/src/test/java/com/google/api/generator/gapic/protoparser/ResourceReferenceParserTest.java
+++ b/src/test/java/com/google/api/generator/gapic/protoparser/ResourceReferenceParserTest.java
@@ -48,6 +48,7 @@ public void setUp() {
   public void parseParentResourceName_createFromPattern() {
     String resourceNamePackage = String.format("%s.common", MAIN_PACKAGE);
     String domainName = "cloudbilling.googleapis.com";
+    String description = "This is the resource name description";
     String resourceTypeString = String.format("%s/BillingAccount", domainName);
     String parentResourceTypeString = String.format("%s/Project", domainName);
     Map<String, ResourceName> patternsToResourceNames = new HashMap<>();
@@ -59,6 +60,7 @@ public void parseParentResourceName_createFromPattern() {
             MAIN_PACKAGE,
             resourceNamePackage,
             resourceTypeString,
+            description,
             patternsToResourceNames);
     assertTrue(parentResourceNameOpt.isPresent());
 
@@ -67,6 +69,7 @@ public void parseParentResourceName_createFromPattern() {
     assertEquals(Arrays.asList(parentPattern), parentResourceName.patterns());
     assertEquals(parentResourceTypeString, parentResourceName.resourceTypeString());
     assertEquals(resourceNamePackage, parentResourceName.pakkage());
+    assertEquals(description, parentResourceName.description());
     assertEquals(
         TypeNode.withReference(
             VaporReference.builder()
@@ -93,6 +96,7 @@ public void parseParentResourceName_parentResourceNameExists() {
         ResourceReferenceParser.parseParentResourceName(
             "projects/{project}/folders/{folder}/documents/{document}",
             MAIN_PACKAGE,
+            null,
             MAIN_PACKAGE,
             "cloudresourcemanager.googleapis.com/Document",
             patternsToResourceNames);
@@ -109,6 +113,7 @@ public void parseParentResourceName_badPattern() {
         ResourceReferenceParser.parseParentResourceName(
             "projects/{project}/billingAccounts",
             MAIN_PACKAGE,
+            null,
             MAIN_PACKAGE,
             "cloudbilling.googleapis.com/Feature",
             new HashMap<String, ResourceName>());